mineral

Quartz

Silicon Dioxide (SiO2)

Hardness of 7 on the Mohs scale, typically white, milky, or clear in color, vitreous to greasy luster, trigonal crystal system, conchoidal fracture with no true cleavage, specific gravity of 2.65.

Identified July 31, 2026More mineral →

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Physical properties

Hardness of 7 on the Mohs scale, typically white, milky, or clear in color, vitreous to greasy luster, trigonal crystal system, conchoidal fracture with no true cleavage, specific gravity of 2.65.

Formation & geological history

Formed in a wide variety of geological environments, including igneous, metamorphic, and sedimentary rocks. It is a major component of pegmatites and hydrothermal veins.

Uses & applications

Used in electronics, watches, glassmaking, abrasives, and as a semi-precious gemstone or mineral specimen for collectors.

Geological facts

Quartz is one of the most abundant minerals found in the Earth's continental crust. It exhibits piezoelectric properties, meaning it can generate an electrical charge under mechanical stress.

Field identification & locations

Easily identified in the field by its high hardness (scratches glass), lack of cleavage, and conchoidal fracture. Found worldwide in nearly all types of geological formations.